host: john, thanks for your call. reminder, we are going to show you all of the testimony, nearly four hours of john kerry before the senate foreign relations committee, tonight at 8:30 eastern here on c-span. one of the issues that john kerry raised in his opening statement was the u.s. policy towards iran and the issue of containment. here's what he had to say. >> the president has made it definitive. we will do what we must do to prevent iran from obtaining a nuclear weapon. and i repeat here i repeat here today, our policy is not a containment, it is prevention. the clock is ticking on our efforts to obtain responsible compliance. this administration, working with congress and an unpresence in the international coalition, has put in place crippling sanctions on iran. mr. chairman, you have been a leader in that effort and i know will continue to be. president obama has stated again and again, and i want to emphasize this -- he and i prefer a diplomatic resolution to this challenge, and i will work to give diplomac